This invention relates to fire prevention sprinklers for distributing liquid in an environment which is subject to a fire hazard.
Most conventional fire prevention sprinklers consist of a sprinkler body connected to a liquid supply pipe to receive fire extinguishing liquids such as water and having a heat-responsive valve arrangement blocking a passage in the sprinkler body which is set to open the passage when the temperature in the vicinity of the sprinkler exceeds a selected value. In order to distribute the water emerging from the sprinkler passage throughout the area to be protected, the sprinkler includes a deflector supported from the sprinkler body, usually by a frame consisting of two arms projecting beyond the sprinkler passage on opposite sides of the path of emerging water. Alternatively, the deflector may be supported from the sprinkler body by sliding pins rather than fixed arms, allowing the deflector to be optimally positioned automatically and concurrently with the operation of the sprinkler as is required with certain types of concealed sprinklers.
In many cases, the sprinkler deflector consists of a substantially planar disk positioned perpendicularly to the sprinkler passage to distribute water impinging on the deflector radially outwardly in the direction parallel to the plane of the disk. The deflector is usually formed with radially extending slots which permit a portion of the impinging water to pass through the disk, i.e., downwardly toward the floor of the protected area when the sprinkler is of the pendent type suspended from a ceiling. Deflectors of this type are described, for example, in the Meyer et al. U.S. Pat. Nos. 5,366,022 and 5,579,846. In many instances, however, it is desirable to provide a higher water density over the region to be protected by the sprinkler than can be provided by such sprinklers in order to assure adequate protection in particular situations such as, for example, rack storage of items such as plastics and other flammable items in corrugated containers.